Investigators looking into possibility some people within the company knew about the late 2014 theft of information of at least 500 million user accounts. It isn’t clear if this data is from the 2014 hack or from another breach. Forensic experts are also investigating whether an intruder created cookies that could have enabled such intruder to bypass the need for a password to access certain users accounts or account information. The company recorded expenses of $1 million related to the hack in the quarter ended Sept. 30. The company is facing 23 proposed consumer class-action lawsuits following the hack.”]
Source: https://www.csoonline.com/article/3140149/yahoo-investigating-if-insiders-knew-of-hack.html